GCOS /jee'kohs/ n. A quick-and-dirty clone of System/360 DOS that emerged from GE around 1970;

GCOS /jee'kohs/ n.

A quick-and-dirty clone
of System/360 DOS that emerged from GE around 1970; originally
called GECOS (the General Electric Comprehensive Operating System).
Later kluged to support primitive timesharing and transaction
processing. After the buyout of GE's computer division by
Honeywell, the name was changed to General Comprehensive Operating
System (GCOS). Other OS groups at Honeywell began referring to it
as `God's Chosen Operating System', allegedly in reaction to the
GCOS crowd's uninformed and snotty attitude about the superiority
of their product. All this might be of zero interest, except for
two facts: (1) The GCOS people won the political war, and this led
in the orphaning and eventual death of Honeywell Multics, and
(2) GECOS/GCOS left one permanent mark on Unix. Some early Unix
systems at Bell Labs used GCOS machines for print spooling and
various other services; the field added to /etc/passwd to
carry GCOS ID information was called the `GECOS field' and
survives today as the pw_gecos member used for the user's
full name and other human-ID information. GCOS later played a
major role in keeping Honeywell a dismal also-ran in the mainframe
market, and was itself mostly ditched for Unix in the late 1980s
when Honeywell began to retire its aging big iron designs.